chemical formula: [-NH (CH2) 6-nhco (CH2) 4co] n-
properties
translucent or opaque opalescent crystalline polymer with plasticity. The density is 1．15g／cm3. Melting point is 252℃. Brittle temperature -3℃. The thermal decomposition temperature is greater than 35℃. Continuous heat resistance of 8-12℃, balanced water absorption of 2.5%. It can resist acid, alkali, most inorganic salt aqueous solutions, haloalkane, hydrocarbon, ester and ketone, but it is easily soluble in polar solvents such as phenol and formic acid. It has excellent wear resistance, self-lubrication and high mechanical strength. However, the water absorption is large, so the dimensional stability is poor.
the appearance is white or yellow granules
density (g/cm3) 1.1-1.14
tensile strength (MPa) 6.-8.
Rockwell hardness 118
impact strength (kJ/m2) 6-1
static bending strength (KJ/m2) 6-1 < 5-6
Bending elastic modulus (MPa) 2～3
Volume resistivity (ω cm) 1.83× 115
Dielectric constant 1.63
Application
Widely used in manufacturing parts of machinery, automobiles, chemical and electrical devices, such as gears, rollers, pulleys, etc. It can also be made into film and used as packaging material. In addition, it can also be used to make medical devices, sporting goods, daily necessities and so on.
purified terephthalic acid (PTA), with a relative molecular weight of 166.13 and a structural formula of HOOC[C6H4]COOH, is a white powdery crystal at room temperature, which is non-toxic and flammable. If it is mixed with air, it will burn in case of fire within a certain limit. Polyethylene terephthalate (PET) is obtained by polycondensation of high-purity PTA with ethylene glycol (EG), and it can also react with 1,4- ethylene glycol or 1,4- cyclohexanedicarboxylic acid to form the corresponding ester, which is mainly used to produce polyester. Polyester fiber is the most important variety of synthetic fiber, accounting for nearly 8% of the world's total synthetic fiber output. In China, polyester fiber produced with polyester as raw material has exceeded 8% of the total synthetic fiber output. In addition, the amount of PTA consumed by polyester in the production of non-fiber products has increased rapidly recently, and the amount of polyester in the non-fiber field has continued to increase. At present, the products are mainly used for esterification polymerization with ethylene glycol to produce polyester fiber with short polyester chips, which is widely used in textiles. In addition, polyester is also used in the production of film, paint and polyester plastics.
the application of PTA is relatively concentrated. More than 9% of PTA in the world is used to produce polyethylene terephthalate, and the rest is used as raw materials for polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) and other products.
PTA production process can be divided into two parts: oxidation unit and hydrofining unit. Using acetic acid as solvent, raw material p-xylene is oxidized into crude terephthalic acid by air under the action of catalyst, and then crystallized, filtered and dried in turn to obtain crude product; Crude terephthalic acid is hydrogenated to remove impurities, then crystallized, centrifugally separated and dried to obtain PTA products.
purified terephthalic acid is the main raw material for producing polyester fiber, resin, film and container resin, and is widely used in chemical fiber, container, packaging, film production and other fields. The raw material of PTA is xylene, and the raw material of xylene is petroleum. PTA is the raw material of polyester, and polyester is the raw material of polyester, while 8% of chemical fiber is polyester, and chemical fiber accounts for 36% of the raw material of textile industry.
[1] China's demand for PTA futures
At present, there are no PTA futures varieties abroad. China is the largest PTA consumer market in the world, and its import dependence is about 5% at present. The introduction of PTA futures will help all parties concerned to avoid the risk of price fluctuation and further compete for the pricing power of PTA.
At present, China is the largest PTA consumption market in the world. Last year, the output of PTA in China was 5.5 million tons, and the consumption exceeded 1 million tons. It is estimated that the demand will reach 17 million tons by 21. A large part of the domestic PTA market needs to be made up by imports. Due to the expansion of market demand and the rise of oil price, PTA market price has been rising in recent years. Due to the lack of hedging tools, related enterprises have suffered great market risks.
the future of PTA futures
PTA (purified terephthalic acid) futures have landed on Zhengzhou Commodity Exchange. The listing of PTA futures has been approved by the State Council.
PTA price
PTA cost price = .655× px price +12
PTA cost price = .655× px price +12. Among them, the price of .655×PX is the cost of raw materials, and 1,2 yuan is various production expenses.
(1) raw material cost of PTA production
raw material cost of PTA =.655*PX price
(2) direct processing cost of unit product is about 375 yuan/ton
(3) packaging cost of unit product is about 45 yuan/ton
(4) labor cost of unit product is about 2 yuan/ton
(5). Unit product depreciation is about 35 yuan
(6) unit product freight is about 5 yuan/ton
(7) unit product maintenance and management costs are estimated at 6 yuan/ton
(8) total pre-tax cost of PTA production: .655×PX price+1,
Note: PX, also known as p-xylene, is an important organic chemical raw material.
PTA import price calculation:
The calculation formula is PTA 57 USD/ton * RMB exchange rate * * * VAT * * * 6.5% tariff+terminal charges about 15 yuan/ton =553.62 yuan/ton.
PTA import price = FOB (fob) × converted RMB exchange rate × value-added tax × tariff 6.5%+ terminal charges about 15 yuan/ton
PTA import tariff will be reduced year by year. In 22, the tariff of PTA in China was 12.8%, and it took off and landed at 11.8% according to the tariff concession schedule on January 1, 23. In 25, the import tariff of polyester chain products: p-xylene (PX), purified terephthalic acid (PTA) and polyethylene terephthalate (PET) was reduced by .5%-1%. The import duty of PTA was reduced by .5% to 6.5% based on the tax rate in 24.
PTA is the activity of prothrombin in medicine.
another meaning of PTA
Abbr.
= parent-teacher association (USA) (student) parent-teacher association.